Are invasive species most successful in habitats of low native species richness across European brackish water seas?   总被引：5，自引：0，他引：5  

Marjo Paavola  Sergej Olenin  Erkki Leppkoski 《Estuarine, Coastal and Shelf Science》2005,64(4):738-750

European brackish water seas (Baltic Sea, Black Sea and Sea of Azov, Caspian Sea) are subject to intense invasion of non-indigenous species (NIS). In these seas, salinity is the most important range limiting factor and native species seem to reach a minimum species richness at intermediate salinities. This trend, revealed by Remane in 1934 and later on confirmed by many other scientists, was compared to the salinity range of already established NIS in the European brackish water seas. It turned out that most NIS are well adapted to the salinities holding lowest native species richness, already in their native area, and that NIS richness maximum in brackish water seas occurs in the salinity intervals of native species richness minimum. A predictable pattern in the salinity range of NIS can be used as a tool in initial risk assessment of future invasions in brackish water seas, especially when mapping highly potential donor and recipient areas. A product of empty niches, suitable environmental conditions, and availability of proper vectors might be the most effective predictor for the invasibility of brackish water areas.  相似文献   

Calculation Of The Height Of The Stable Boundary Layer In Practical Applications     

Sergej Zilitinkevich  Alexander Baklanov 《Boundary-Layer Meteorology》2002,105(3):389-409

Currently used and newly proposed calculation techniques for the heightof the stable boundary layer (SBL), including the bulk-Richardson-numbermethod, diagnostic equations for the equilibrium SBL height, and a relaxation-typeprognostic equation, are discussed from the point of view of their physical basis andrelevance to experimental data. Among diagnostic equations, the best fit to data exhibits an advanced Ekman-layer height model derived recently with due regard to the role of the free-flow stability. Its extension to non-steady regimes provides a prognostic equation recommended for use in practical applications.  相似文献   

Sandstone Turning by Abrasive Waterjet     

Petr Hlaváček  Ján Cárach  Sergej Hloch  Karol Vasilko  Dagmar Klichová  Jiří Klich  Dominika Lehocká 《Rock Mechanics and Rock Engineering》2015,48(6):2489-2493

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Wear Assessment of Conical Pick used in Coal Cutting Operation     

Saurabh Dewangan  Somnath Chattopadhyaya  Sergej Hloch 《Rock Mechanics and Rock Engineering》2015,48(5):2129-2139

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Resistance law,effective roughness length,and deviation angle over hilly terrain     

S. Emeis  S. S. Zilitinkevich 《Boundary-Layer Meteorology》1991,55(1-2):191-198

In this note, we derive from the resistance law of Rossby number similarity theory the expressions for the drag coefficient and the deviation angle for strongly unstable and strongly stable stratifications. The extension of the applicability of the resistance laws to inhomogeneous terrain is discussed. A determination of the deviation angle over inhomogeneous terrain from a numerical experiment is presented.On leave from: Institute of Limnology, Academy of Sciences of the USSR, 196199 Leningrad.  相似文献   

Velocity profiles,the resistance law and the dissipation rate of mean flow kinetic energy in a neutrally and stably stratified planetary boundary layer     

S. S. Zilitinkevich 《Boundary-Layer Meteorology》1989,46(4):367-387

The logarithmic + polynomial approximation is suggested for vertical profiles of velocity components in a planetary boundary layer (PBL) at neutral and stable stratification. The resistance law functions A and B are determined on the basis of this approximation, using integral relations derived from the momentum equations, the Monin-Obukhov asymptotic formula for the wind profile in a stably stratified near-surface layer and the known expressions for the PBL depth. This result gives a realistic and convenient method for calculating the surface friction velocity and direction and the total dissipation rate of mean flow kinetic energy in terms of geostrophic velocity, buoyancy flux at the surface, the roughness parameter and the Coriolis parameter. In the course of these derivations a review is given of current views on the main problems of the neutral and stable PBL.  相似文献   

Shear convection     

S. S. Zilitinkevich 《Boundary-Layer Meteorology》1973,3(4):416-423

The paper discusses convection in the presence of wind shear, a condition analysed previously by Zilitinkevich (1971). This region (between the forced and fully developed convective layers) was also considered by Betchov and Yaglom (1971). In the present paper the author endeavors to develop a consistent analysis from the basic hypothesis of a very weak interaction between the vertical convective motions and mechanical turbulence, employing a new similarity model of the turbulent regime. Additional experimental data are introduced. Unlike the notation used in the references quoted above, this regime is termed shear convection rather than free convection. The latter is traditionally regarded as synonymous with the terms pure or fully developed convection.  相似文献   

Subject Index     

S. S. Zilitinkevich 《Boundary-Layer Meteorology》2002,105(3):511-510

Subject Index

Subject Index  相似文献   

Tangling Turbulence and Semi-Organized Structures in Convective Boundary Layers     

T. Elperin  N. Kleeorin  I. Rogachevskii  S. S. Zilitinkevich 《Boundary-Layer Meteorology》2006,119(3):449-472

A new mean-field theory of turbulent convection is developed based on the idea that only the small-scale region of the spectrum is considered as turbulence, whereas its large-scale part, including both regular and semi-organized motions, is treated as the mean flow. In the shear-free regime, this theory predicts the convective wind instability, which causes the formation of large-scale semi-organized motions in the form of cells. In the presence of wind shear, the theory predicts another type of instability, which causes the formation of large-scale semi-organized structures in the form of rolls and the generation of convective-shear waves propagating perpendicular to the convective rolls. The spatial characteristics of these structures, such as the minimum size of the growing perturbations and the size of perturbations with the maximum growth rate, are determined. This theory might be useful for understanding the origin of large-scale cells and rolls observed in the convective boundary layer and laboratory turbulent convection  相似文献   

Single-binary star separation by ultraviolet color index diagrams     

Oleg?MalkovEmail author  Aleksej?Mironov  Sergej?Sichevskij 《Astrophysics and Space Science》2011,335(1):105-111

Detection of a composite flux in photometry can serve as an indication of a photometrically unresolved binarity and can contribute to the parameterization of the components of binary systems. A main goal of the present study is to develop a method of automatic photometric detection of binaries, based on multi-color photometry, theoretical stellar spectral energy distributions and general understanding of binary evolution. In particular, we consider an ultraviolet photometry where, in combination with optical and infrared photometry, interstellar reddening can be easier distinguished from temperature reddening.  相似文献